This invention relates to a method of termite-proofing sub-floor areas of buildings employing pipe systems for infusing termiticide into adjacent ground.
In Australian Patent No. 583405, we have described a particularly effective method and system for termite-proofing buildings having a concrete foundation and a plastic waterproof sheet beneath the foundation and overlying ground adjacent the foundation. The termite-proofing method is implemented through a pipe system comprising two sub-systems of tubes. The primary tube sub-system comprises a network of tubes lying at regular spacings throughout the floor area, at least some of the tubes lying adjacent the foundation of the building and beneath the plastic waterproof sheet. The secondary tube sub-system is located in the vicinity of the perimeter of the foundation. Ready access to both of these tube sub-systems is achieved by means of at least one tube extension having an and which is readily accessible from above ground and which is closed by a removable closure cap. In this way, a liquid termiticide can easily be poured into the tube sub-systems for the initial treatment, and also for any re-treatments which may be necessary. The tubes of both tube sub-systems are perforated by a plurality of apertures spaced along their lengths, the apertures being of such size and spacing that, when the termiticide is injected (preferably high volume, low pressure) through the above-ground tube extension, it flows through the apertures and infuses the ground adjacent the foundation of the building.
Despite the undoubted effectiveness of this system, its relatively high cost is a drawback in relation to economy housing developments. There is a need for a cheaper alternative which still allows for re-treatment, particularly of critical areas (ie the areas which are most prone to attack by subterranean termites). As recommended in Australian Standard, the contents of which are hereby incorporated by reference 3660.1-1995, the critical areas are eg xe2x80x9cwetxe2x80x9d areas, such as bathrooms, toilets and kitchens, perimeter edges and construction joints.
Although in some situations, the termite-proofing system of the present invention may be used to apply both the initial chemical barrier and for any re-treatments which may be necessary, it is generally recommended that the system merely be used for re-treatments. In most circumstances, it will be necessary to apply an initial chemical barrier by conventional means, such as hand-spraying of termiticide.
At present, the termiticides for Australian use are registered by the National Registration Authority for Agricultural Chemists. Such termiticides should be used to re-treat high-risk areas every three to ten years. Future chemical developments may require more or less frequent re-application to these critical areas.
It is the object of the present invention to provide a convenient and relatively cheap method of treatment or re-treatment for significant eradication of termites in the sub-floor area and adjacent thereto.
With this object in view, the present invention provides a pipe system for termite-proofing a sub-floor area of a structure having a foundation penetrated by at least one penetration comprising:
(a) a primary tube system comprising at least one tube located substantially at or adjacent the perimeter of the building;
(b) a secondary tube system comprising at least one tube adjacent at least one penetration; and
(c) means for charging both primary and secondary tube system with insecticide;
wherein the tube systems comprise tubes perforated along a substantial portion of their length by a plurality of apertures of such size and spacing that insecticide flows through the apertures and infuses the adjacent ground.
Typically, the penetration takes the form of a plumbing pipeline but it could take the form of a load bearing member or pier in a suspended slab or wooden floor construction or the like.
The charging means may include a tube extension in communication with at least one of the primary tube system and secondary tube system having an end which is closed by a removable closure cap. Preferably, the primary and secondary tube systems are interconnected, with a single tube extension providing insecticide to both. The tube extension end is advantageously readily accessible from above ground and the closure cap is such as to maintain a pressure in the tube systems sufficient to enable infusion of termiticide into the adjacent ground. Termiticide may be injected or pumped into the tube extension and ultimately infused into the ground through the pipe system.
Preferably, the insecticide is pumped into the system through the charging means under a pressure of eg 10 to 40 kPa. In particular, for 40 mm pipes, the preferred pressure for treating and flushing is 14 to 16 kPa, whereas for 15 mm pipes it is 27 to 30 kPa.
The primary tube system may include tubes generally defining the perimeter of a building foundation. Tubes may be provided generally adjacent the inner edge of the foundation, an inner perimeter pipe, and/or generally adjacent the external perimeter of the foundation, an external perimeter pipe. Both are advantageously provided together in the case of an infill/footing foundation. In the case of a monolithic slab, the inner perimeter tube may be omitted. The perimeter pipe(s) may be laid generally parallel the perimeter of the foundation. Other foundation types commonly used in United States and Japan are maybe termite proofed in accordance with the present invention.
The secondary tube system includes at least a tube adjacent a penetration at the least though it is generally preferable that each penetration is at least substantially surrounded, and more preferably completely surrounded, by a tube or tubes in the form of a grid system fed with termiticide either from a perimeter tube forming part of the primary tube system (inner or external) or from a manifold or common supply communicating with the charging means and delivering termiticide to the various penetrations or xe2x80x9cwetxe2x80x9d areas of the structure. Any manifold or supply may be located generally centrally of the building or structure though this is not mandated. The secondary tube system could be fed either from an inner or external perimeter tube with which it conveniently is directly connected. The secondary tube system is most conveniently integral with the charging means and it is not desirable that each tube system protecting each xe2x80x9cwetxe2x80x9d area be separately charged by separate charging means. Common supply is preferred. A major advantage of the system is its integral nature, at least insofar as the protection of each penetration or xe2x80x9cwetxe2x80x9d area is concerned.
The pipe system of the invention is not confined in its nature to the particular type of foundation construction employed, concrete or otherwise. It may also form part of a termite-proofing solution involving other means of termite eradication. The invention preferably involves use of plastics such as PVC for manufacture of the tubes which has advantages in terms of costs and ready adaptation to different types of building structure without complex redesign and adjustment of pipe layout.
In another aspect, the invention is a means for termite-proofing a sub-floor area of a building having a concrete foundation penetrated by one or more plumbing pipelines, and a waterproof sheet beneath the foundation and overlying ground adjacent the foundation comprising:
(a) a primary tube system comprising at least one tube located at or adjacent the perimeter of the building; and
(b) a secondary tube system comprising at least one tube adjacent one of said plumbing pipeline(s) and beneath said waterproof sheet,
said primary tube system and said secondary tube system each joining into a tube extension having an end which is readily accessible from above ground and which is closed by a removable closure cap, and said tubes being perforated along their length by a plurality of apertures, the apertures being of such size and spacing that, when liquid insecticide is injected through a said tube extension, it flows through said apertures and infuses the adjacent ground.
An alternative to a treatment or re-treatment system such that as that of the present invention would be to disrupt the building by drilling and injecting termiticide through the slab, including any tiles, slate, marble etc. Such a procedure is expensive, messy, obtrusive and dangerous.